/Engine/Source/Runtime/Core/Public/Misc/App.h
Checks whether this application can render anything. Certain application types never render, while for others this behavior may be controlled by switching to NullRHI. This can be used for decisions like omitting code paths that make no sense on servers or games running in headless mode (e.g. automated tests).
true if the application can render, false otherwise.
static bool CanEverRender()